Once a Hero - S4-E8
Other mistake: Ducky states that the Bronze Star was for Valor. However, the bronze V that signifies the star was for Valor is not present. There is no way Ducky could know it was for Valor. (00:05:20)
Once a Hero - S4-E8
Other mistake: When Abby is talking to the microscope guy during the line "you understand without having to go find a dictionary" there is a half second flash of another shot with DiNozzo walking off camera in a street setting. Maybe just a encoding error on Netflix but it persisted after reloading. (00:23:45)
Chosen answer: It is never stated, however she must have been there several years if she is on presidential detail.